Recent findings from the Multimodal Treatment Study of ADHD Children (MTA) reveal that ADHD children treated pharmacologically via a university-based pharmacological intervention have improved treatment outcomes compared to ADHD children treated pharmacologically in community settings. This finding is not surprising since several studies have documented that the majority of community-based physicians fail to utilize systematic, evidence-based procedures with regard to evaluation and treatment decisions. In accord with the "Bridging Science and Service" report issued by the National Institutes of Mental Health, the proposed study will translate evidence-based assessment and treatment procedures utilized in the MTA to community-based practices. Community-based pediatricians will be targeted since pediatricians are the most frequent providers of pharmacological treatment to ADHD children. The primary goal of the proposed research is to assess the feasibility, utility, and effectiveness of a university-based assistive infrastructure (AI) in promoting the implementation of evidence-based practice procedures among community pediatricians. The AI is comprised of three main components: 1) educating pediatricians about the assessment and treatment of ADHD children; 2) providing state-of- the-art assessment and treatment resources to pediatric practices; and 3) availing ongoing consultative services to pediatricians. The study will occur in three phases. Phase I, the AI refinement phase, will utilize two pediatric practice groups and examine pediatrician compliance, problem-solve barriers to implementation, and streamline the operations of the AI. Phase II, a randomized trial, will include ten pediatric group practices (40 pediatricians and 160 children) that will be randomly assigned to either the AI or a comparison group. Pediatricians assigned to the AI group will have access to all AI components while comparison group practices will function without these services (treatment as usual). Phase III will repeat the intervention in the comparison group practices. The study design will allow for between-groups and within-group comparisons of pediatricians' utilization of the infrastructure, pediatricians' practice behaviors, child outcomes, consumer satisfaction, and costs.